RT Journal Article SR Electronic T1 High Performance Liquid Chromatography Survey on Changes in Pigment Content in Ripening Grapes of Syrah. An Approach to Anthocyanin Metabolism JF American Journal of Enology and Viticulture JO Am J Enol Vitic. FD American Society for Enology and Viticulture SP 77 OP 83 DO 10.5344/ajev.1986.37.1.77 VO 37 IS 1 A1 J. P. Roggero A1 S. Coen A1 B. Ragonnet YR 1986 UL http://www.ajevonline.org/content/37/1/77.abstract AB Three clones of Syrah grapes were studied during maturation using high performance liquid chromatography in order to observe changes in composition and to follow the evolution of the main anthocyanin contents. The reported percentages and contents allow the studied clones to be compared and also show kinetic disparities in anthocyanin and sugar formation. Except for cyanidin, which is the precursor of the other pigments, the anthocyanin composition is quickly set up after véraison and remains nearly stable until the grapes mature. Nevertheless, delphinidin drops in concentration as soon as biosynthesis ceases, and the percentage in malvidin gradually increases. Every sudden variation indicates an anomaly in pigment metabolism and means that the formation process is coming to an end. In an ideal behavior, the levels of cyanidin and delphinidin first peak three to four weeks after véraison, then decrease rapidly, whereas peonidin and malvidin are always being formed. The level of petunidin peaks by the third week and is stable thereafter. Changes in concentration of malvidin 3-glucoside esters correspond to those of the glucoside.